Why Macy’s relented to an early Thanksgiving opening

FORTUNE — By the strings of Snoopy’s giant parade balloon, Macy’s has been tied to Thanksgiving for decades. But shopping at its stores on Turkey Day? Totally off-limits. Until now.

In a statement released late Monday announcing its Black Friday deals, the retail chain said that most of its 800 stores would open at 8 p.m. on Thanksgiving Day, “after families across the country have finished their holiday meals and celebrations.”

Macy’s M has traditionally opened at midnight on Black Friday, and in recent years, it had been one of the few big retailers to buck the so-called holiday creep in which stores kicked off their holiday sales on Thanksgiving Day itself. The trend began two years ago when Toys R Us opened its doors at 9 p.m. on Thanksgiving Day. Last year, Wal-Mart wmt, Target tgt, and Sears shld pulled the same move, welcoming shoppers on Thanksgiving evening and staying open through Black Friday.

The moves triggered backlash against the stores, which were criticized for infringing on the holiday and forcing employees to cut short family celebrations. Retail employees formed petitions against the Thursday shopping hours. One petition on change.org that asked Target to “give Thanksgiving back to families” and delay its planned 9 p.m. opening garnered more than 376,000 signatures but ultimately failed.

Twitter was abuzz on Tuesday with criticism of Macy’s decision. “Macys is breaking tradition. For 155 years they’ve been closed on Thanksgiving Day. This year they’ll be open at 8 p.m. Absurd,” one Tweet said.

But Americans who call retailers Grinches can only blame themselves. Sympathy for retail employees and reverence for Thanksgiving as a family holiday have not kept shoppers away from early Black Friday openings. Twenty-eight percent of Thanksgiving weekend shoppers were at stores by midnight on Black Friday last year, compared to 24.4% the year before, according to a National Retail Federation survey conducted by BIGinsight. As a whole, Black Friday weekend — which includes Thanksgiving Day — drew 247 million shoppers in 2012, up from 226 million in 2011.

And this year’s ploys to lure customers into stores while the turkey is still warm could be even more persuasive. Retailers are turning to earlier shopping hours and bigger deals to try to make up for lackluster consumer sentiment, says David Bassuk, co-head of the retail practice at consultancy AlixPartners. The overall index on consumer sentiment slipped to 77.5 in September — the lowest final reading in five months. Political gridlock in Washington and economic indicators have given stores cause for concern, says Bassuk. “It’s not surprising that retailers are pulling out all stops.”

Shopping on Turkey Day could also offer benefits beyond a boost to retailers’ bottom lines. NRF President and CEO Matthew Shay said last year that shopping had been integrated into Thanksgiving festivities and that “whole families are going [to the stores].” Bassuk agrees. Thanksgiving is a time when people are “open to doing things together, including shopping,” he says.

Fighting over Martha Stewart casserole dishes — discounted by 60%! — is now a family affair.